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本文研究使用Ishikawa迭代格式求实李普希兹映射的不动点,指出该迭代格式仅具线性收敛率;对于参变量序列{αn}、{βn}所取的不同的值,比较了迭代格式的收敛速度.在给出加速因子定义的基础上,本文给出了加速收敛的一个充分条件. 相似文献
53.
Hyesu Lee Eunmi Jo Kyung Yoon Chung Dongjin Byun Seung Min Kim Wonyoung Chang 《Angewandte Chemie (International ed. in English)》2020,59(6):2385-2391
The structural stability of cathode materials during electrochemical reactions, in particular, under high‐rate discharge, is pertinent to the design and development of new electrode materials. This study investigates the structural inhomogeneity that develops within a single LiNi0.835Co0.15Al0.015O2 (NCA83) particle during a fast discharging process under different cutoff voltages. Some of the NCA83 particles discharged from a high cutoff voltage (4.8 V) developed surface areas in which the layered structure was recovered, although the interiors retained the degraded spinel structure. These micro‐ and nano‐scale structural inversions from high cutoff voltage seem highly correlated with structural evolutions in the initial charged state, and may ultimately degrade the cycling stability. This study advances understanding of the structural inhomogeneity within primary particles during various electrochemical processes and may facilitate the development of new Ni‐rich cathode materials. 相似文献
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Water disinfection tanks such as chlorine and ozone contactors typically consist of multiple compartments featuring a serpentine flow pattern. Due to the complex hydrodynamics, the design and optimization of these tanks are often carried out by employing computational fluid dynamics (CFD) simulations. The present study demonstrates the influence of certain modeling aspects when the widely used Reynolds-Averaged Navier Stokes (RANS) based CFD approach to predict hydrodynamics and disinfection performance is employed. Three different contact tank geometries are examined numerically using RANS. The time-averaged velocity predictions are reasonably accurate when compared to validation data. However, in baffled contact tanks, the time-averaged flow differs quite significantly from the instantaneous flow, with the consequence that RANS-based models require careful calibration of the turbulent mixing parameter, i.e., the turbulent Schmidt number, when computing transport of solutes. 相似文献
57.
A numerical simulation of reaction injection molding (RIM) of polymeric foam is developed, using a finite volume method (FVM). In this study we predict mold filling with a variable‐density fluid that fills a mold by self‐expansion. We deal with two‐dimensional, isothermal cases. With the assumptions of ideal mixing and rapid bubble nucleation, the foam is modelled as a continuum with a time‐dependent density. The continuum is assumed to be a Newtonian fluid. We develop a pressure‐based FVM for unstructured meshes that includes the SIMPLE algorithm with treatment of fluid compressibility. Cell‐based, co‐located storage is used for all physical variables. To treat the moving interface, an explicit high‐resolution interface capturing method is used. Foam flow in a slit is investigated, and the numerical calculations are in good agreement with an approximate analytic solution. For fountain flow in a rectangular cavity, the shape of the flow front is flatter and the traces of the particles are more complicated for an expanding foam than for a constant‐density fluid. An example of mold filling by an expanding foam demonstrates the geometric flexibility of the method. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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Dong Kyu Kim Hyobin Jeong Jingi Bae Moon-Yong Cha Moonkyung Kang Dongjin Shin Shinwon Ha Seung Jae Hyeon Hokeun Kim Kyujin Suh Mi-Sun Choi Hoon Ryu Seong-Woon Yu Jong-Il Kim Yeon-Soo Kim Sang-Won Lee Daehee Hwang Inhee Mook-Jung 《Experimental & molecular medicine》2022,54(9):1461
Mitochondria in neural progenitors play a crucial role in adult hippocampal neurogenesis by being involved in fate decisions for differentiation. However, the molecular mechanisms by which mitochondria are related to the genetic regulation of neuronal differentiation in neural progenitors are poorly understood. Here, we show that mitochondrial dysfunction induced by amyloid-beta (Aβ) in neural progenitors inhibits neuronal differentiation but has no effect on the neural progenitor stage. In line with the phenotypes shown in Alzheimer’s disease (AD) model mice, Aβ-induced mitochondrial damage in neural progenitors results in deficits in adult hippocampal neurogenesis and cognitive function. Based on hippocampal proteome changes after mitochondrial damage in neural progenitors identified through proteomic analysis, we found that lysine demethylase 5A (KDM5A) in neural progenitors epigenetically suppresses differentiation in response to mitochondrial damage. Mitochondrial damage characteristically causes KDM5A degradation in neural progenitors. Since KDM5A also binds to and activates neuronal genes involved in the early stage of differentiation, functional inhibition of KDM5A consequently inhibits adult hippocampal neurogenesis. We suggest that mitochondria in neural progenitors serve as the checkpoint for neuronal differentiation via KDM5A. Our findings not only reveal a cell-type-specific role of mitochondria but also suggest a new role of KDM5A in neural progenitors as a mediator of retrograde signaling from mitochondria to the nucleus, reflecting the mitochondrial status.Subject terms: Neural stem cells, Neural stem cells, Alzheimer''s disease 相似文献
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In this paper, a class of reaction diffusion processes with general reaction rates is studied. A necessary and sufficient
condition for the reversibility of this calss of reaction diffusion processes is given, and then the ergodicity of these processes
is proved.
Supported by Ying-Tung Fok Education Foundation and NSFC;
Supported partially by NSFC and by Anhui Education Committee. 相似文献
60.
Routine monitoring of microcystin in natural waters is difficult because the concentration of the toxin is usually lower than the detection limits. As a more sensitive detection method for microcystin, we developed a competitive enzyme-linked immunosorbent assay (ELISA) based on monoclonal antibodies. New monoclonal antibodies against the microcystin leucine-arginine variant (MCLR), a cyclic peptide toxin of the freshwater cyanobacterium Microcystis aeruginosa, were prepared from cloned hybridoma cell lines. We used keyhole limpet hemocyanin (KLH)-conjugated MCLR as an immunogen for the production of mouse monoclonal antibody. The immunization, cell fusion, and screening of hybridoma cells producing anti-MCLR antibody were conducted. In the ELISA test, a microtiter plate coated with MCLR-bovine serum albumin conjugate was incubated with standard microcystin samples. The amount of antibody bound was determined by the reaction of peroxidase-labeled anti-mouse IgG with its substrate, 3,3′,5,5′-tetramethyl benzidine (TMB). Since the ELISA test was highly sensitive, the newly developed ELISA can be suitable for the trace analysis of cyanobacterial hepatotoxins, microcystins in water. The linear responses of monoclonal antibodies with different concentrations of microcystin LR were established between 30 and 1600 pg/mL. 相似文献